Pneumatic hand-hammer.



G. H. STEVENS.

PNEUMATIC HAND HAMMER.

APPLICATION FILED JULYB, 1909 Patented Jun 19153,

SHEET 1 6 am e22 ZZ/Zzxg 1' G. H. STEVENS. PNEUMATIC HAND HAMMER.

APPLICATION FILED JULY 8, 1909.

Patented June 18, 1912.

7 SHEETS-SHEET Z.

F 1E.E.

r M ,W 3 W A C. H. STEVENS.

PNEUMATIC HAND HAMMER.

APPLIGATION FILED JULYB, 1909.

Patented June 18, 1912.

7 SHEETS-SHEET 3.

G. H. STEVENS. PNEUMATIC HAND HAMMER.

APPLICATION FILED JULY 8, 1909. 21, I Patented June 18, 1912.

'1 SHEETS-SHEET 4.

Fi 11 F1915 G. H. STEVENS.

PNEUMATIC HAND HAMMER.

APPLICATION FILED JULY 8, 1909.

Patented June 18, 1912.

'7 SHEETS-SHEET 5- mwam.

lillLlFlillllux 1 2% en 02 02mm? ZZw/ enema Zia? M1??? U. H. STEVENS.

PNEUMATIC HAND HAMMER.

igfigifiyfig 1? APPLICATION I'ILEI? JULYS, 1909. June 18,

7 SHEETSSHEET 6- G. H. STEVENS.

PNEUMATIC HAND HAMMER.

lgggflgglg'i APPLICATION PIIfED JULYB, 19094 Patented 18,

'7 SHEETS-SHEET 7 ,FIQ E5 l; in Fiieunisiio ouinol impact o i 1 oi" imp t o. vaciiu m e apps? or handle emi oi" the tool, has more particular reference to the unployod for uiti .i. ssicl vsoou F stroke of pneumatic ha o. sting chippin ilking, an

The ohjecl of my in sion of c. hancl hammer oi she type referred to which is simple in co LlllCillOl'l, lighter in weight end of g] power than hom mers of like size eon. :zcized lici'etofoie.

Willi foregoing oogecifi in view my improvemenis essenlialiy consist in the use of an sting" sir ctor in ihe edinission v lve situated the op um." or hen- (lle en glof The lool for the. poioose of crest ing :z'vacuum or pantie vacuum on the upper end of the piston to cause the return *stroke 01"? said piston afiez: ihe blow has been struck. This vacuum I may alternatively produce oi the coir-col, one means of a. suitable eonnecfi o. ohs'loliel mining a siteacli vacuum siiu Mei oi distance from the hammer oi' hens mers. By this means only eimosoheric pressure comes in contsc with the lower on tool end of the piston, olmi. further I can (lispense with any air passages for high pres:

accompanying (li'mvino s one in illusrotion of one nvenient ioi-in of pneumatic .lwmlqhsmzner embodying Jill-o present iinprovemenls.

Gihlfifiillifil, GANAEY ISLANDS.

li oteneel Jose 1%, i912.

Milli: loose oml felorenoe numerals designsiellis or similar arts in the several oi iblis scoompanyln j drawings.

llignre 1 is a sectional e ovation through opp oi or him-file end of :i pneumalic lzimlflel embodying my improvements. Fi 2' is s cross sectional elevation through the honzlle enrl of the hammer taken at ri ht *ggles to l fg'. 1. Fig. 3 is a bottom p an oi he conic? part of the valve box. Fig. 4

is cross sectional elevation of the center port of the VillWd'lllOX through the line (4-4),

Fig. 5. is a top plan of the lower part oi ishe valve box. Fig. 6 is a sectional sfilaion taken on the line e-f in Fig.

of tho lower part of the valve box. Fig. 7 is e lop plan of the center poi-inf the valve em. Fig. 8 is a cross sectional elevation of l lie center part of the valve box through linec cl, Fig. 7. Fig. 9 is a, bottom plan lilo lower part of the valve box. Fig. 10 e. sectional elevation on the 11118 g-h in lil 5 of the lower part of lhe valve box. Fig. 11 is a bottom plan of the lop part of the "valve box. Fig. 12 is a cross section through thelop part of the valve box on the line 7ainiFig. 16. Fig. Bis a sections}: eleve. n of the valve through the line 0--;o in

tion of the valve taken on the line 9-4 in 17. Fig. 15 is a. top plan of the top peril of the valve box. Fig. 16 is a sectional elevation of the top part ofthe valve box islzon on the line a m-n in Fig. 12. Fig. 17 is elevation of the valve. Fig. 18 is a cross section of the valve through the line 8; inlfiig. 13. Fig. 19 is a longitudinal section of the complete hammer. Fig. 20 is e half elevation and longitudinal section iston barrel. Fig. 21 is a cross section of the rsliof valve ancl barrel taken on the line 11/ 7) in Fig. 20. Fig. 22 is a cross section of the fist relief valve taken on the line w--m in Fig. 25. Fig. 23 is a plan of the flat relief valve sea Fig. 4 is a cross section oi. tlle bottom end of the barrel taken on the line yz in Fig. 25. Fig. 25 is a longitudinal section of the fiat relief valve and part of barrel. Fig. 26 is a cross section of the handle, and barrel iaken on the 1 line a--Zz in Fig. 1. Fig. 27 is :1v sectional Fig. 14.. Fig; .14 is a cross sec-' a modified form of relief valve sndlhe 1 elevation of the alternative vacuum arrange- .enttaken through the handle end of the hammer. Fig. 28 is a sectional elevation through a slightly modified form of the distributing valve.

For the purpose of description the hammeris supposed to. be standing vertically with the handle upward.

Referring to Figs. 1 and 2 it will be seen that the hammer consists of a handle A, of ordinary type containing an admission valve G, Figs. 1, 27, actuated by a trigger H and held up in the closed position by a springl. The compressed air enters by the screwed nipple J passes through the hole K when the admission valve is depressed and enters into the air hole L which communicates with the annular space M, turned in the top of the cylindrical portion.

. This brings the compressed air to the top part of the valve box B, Figs. 1, 2, 11, 1.2, 15 1s.

The "alve boX consists of three parts, namely, upper part B, Figs. 1, 2, 11, 1.2, 15, 16, center part C, Figs. 1, 2, 3,4, 7, 8, and lower part D, Figs. 1, 2, 5, 6, 9. 10. This valve box contains a distributing Valve F, Figsl 1, 2 i3. 14, 1?, 1s.

Thevalvc box B, C, D, isscatcd on top of the barrel E, Figs. 1, 2, 19, and held in position bythe lower portion of the handle A being screwed on to the end of the barrel E, the threads of the screw being shown in section at N, Figs. 1, 2. After the handle is screwed hard down itis locked in' position by the bolt O. Fig. 1, To allow the bolt 0 to lock the thread N the handle is split uptc P, Fig. 1, so that the diameter of the thread N may be reduced by tightening the bolt 0. This device is common in many machines and is notably used for gripping the carrying rod of a bicycle saddle or the loose headstock of a lathe. A horizontal cross section showing the bolt 0 and thread N is shown in Fig. 26.

The barrel E consists of a thin tube with a screwed portion N at the top end, a relief valve V, F 19 or V, Fig. 20, about the middle, and a. swelled portion at the lower end Q, Figs. 19, 20, into which the tool ll, Figs. 19, 20, is inserted, in this case a snap is shown for riveting. A piston S, shown broken off in Figs. 1 and 2. and entire in Figs. 19, 20, works up and down in the barrel lC, Figs. 1, 2, 19, 20, 28, and is a good fit therein.

The upper part 13 of the valve box, Figs. 1, 2, 11, 12, 1 1,16, contains an air ejector nozzle T, Figs. 1, 12. and an ejector discharge U, Figs. 1, 1.2. This air ejector T,

U, is tor the purpose of creating a vacuum above the piston S in the barrel l3. omprcssed air holes 2, Figs. 2, 11, 12, 15, 1.6, in this case eight in number, pass right through the part B, communicating at their case six in number, communicate fronrthe lower side of the part Bintothe nozzle chamber 7. Figs. 1, 2, 12, 16. The ejector discharge U, Figs. 1, 1.2, is screwed into the part B from the opposite side to the nozzle T and in line with it.

The center part of the valve box C, Figs.

the nozzle from holes 1. 2, 3, 4, 7, 8, contains the Working chamber of the lvalve' F, Figs. 1, 2, 13, 14, 17, 18. Eight compressed air holes 8, Figs. 2, 3, 4, 7,

pass rightthrcugh the part 0, and corre;

spond at their upper ends with the holes 2 in the part B, Figs 2, ll, 12, 15, 16. A cup-shaped holloiv 9,Figs. 1, 2, 4, '7, 8 is turned out of the top of the part C and corresponds with the eduction holes 6 in the lower side of the upper part B. A cylindrical hole 10, Figs. 1, 2, 3, 4, 7, 8, i5 for the upper end of the valve F to Work in. A large cylindrical hole 11, Figs. 1, 2, 3, 4, 8, is for the body of the valve F to work in. A groove 12, Figs. 1, 2, 4, 8, is for conveyance of compressed air to the ejector nozzle. Two holes 13, 13, Figs. 7, 8, are drilled from the top part of C ata slight inclination and enter the groove 12 and are for conveyance of compressed air from groove 12 to holes 5,1), in the lower part of part B Fig. 11, which communicates with the ejector nozzle. A small hole 141, Figs. 2,3,4, 8, allows compressed air to enter from one of the holes 8, Figs. 2, 3, .1;, 7. into'the valve chamber 11. Another small hole 15, Figs. 1, 3, 1, allows air to enter the cylindrical valve hole 11.

The lower part of the valve box I), Figs. 1, 2, 5, 6, 9, 10 has in its upper face a groove or recess 16 to communicate compressed air to the barrel F to drive the piston S down b. way of the hole 18, Figs. 2, 5, 6, 9, 10. Flight U-shapcd cuts 17, Figs. 5, ,6, 10, of the same depth as the groove or recess 16 correspond with the lower endsof the holes 8, Figs. 3, at, 7, in the center part C and are for the purpose of connnunicating compressed air from these holes 8 into the groove or recess 16, Figs. 1, 2, 5, 6, 10. A miter seat 17, Figs. 6, 10, is for seating the dis tributing valve F, and a hole 18, Figs.

6. 9, 10. is for ell'ecting communication be} tween the valve chan'ibers 10, 11, Figs. 4-S

and the barrel E.

The distributing valve F, Figs. 1. 2,

14, 17, 18, lyas an upper portion of small diameter 19, 13, 17, to work in the cylindrical hole 10, Figs. 41, 8, in the center part. Q with a list seating'19, Figs. 13, 17, on the top to sit against the seating 7 in the part 13, Figs. 11, 13, a larger diameter portion ormain body 20, Figs. 13, 14, 17, 18, to Work in the cylindricalchamber 11, Figs. 3, 4, 8, in the center part- C, and a smaller diameter and lower portion 21, Fi 1, 13, 17, to pass into the top of the barrel E. A groove 22, Figs. 13,141, 17, is cut all around the body of the valve and has a small hole 23, 13, 11, which communicates from the top of the main body of valve 20, Figs. 13, 14:, 17, 18, into the groove 22, Figs. 13, 1 1, 17. A large hole 24, Figs. 1, 2, 13, let, 13, traverses the valve from top to bottom through the center and forms the eduction passage of air from thebarrel E. A series of shallow round holes 25, Figs. 13, 17, 18, are spaced around the main body of the valve below the groove 22, Figs. 13, 17, and have for object to make communication between the groqj'ze or recess 16 in the lower part 01' valve box D, Fig. 5, 6,10, and the groove 12 in the center part of valve box C, Figs. 4, 8. A miter edge 26, Figs. 13, 17, is for seating on. the miter seat 17', Figs. 6,10, in the lower part of valve box D.

The relief valve V, Figs. 19, 25,- or V, Figs. 20, 21, on the barrel E may be any form of non-return valve, preferably a thin sheet of steel as at V, Figs. 19, 25, sliding up and down and guided by a pin 30, Figs. 22, 25. Said pin passes through the center of the valve and is inserted into the valve seat 29, F lg. 22, in the small hole 29 drilled to receive it at its bottom end and, said pin is held at its top end in a recessed boss 29,

25, formed in the under part of the guard or cover W, Figs. 19, 25. The valve is held in its place against the seat 29, Figs. 19, 25, by a light spring 30, Figs. 22, 25, and covers the relief holes 28, Figs 19, 25, the whole being covered by a hand guard W, Figs. 19, 25, held in position by four screws X, Figs. 23, 25, in order to keep the operators hand from interfering with the working of the valve. Another efiicient valve is also shown in Figs. 20 and2'l, the valve V being a stout rubber ring surrounding a series of holes 28, Figs. 20, 21, and closing lightly on them by means of its elasticity as its internal diameter is slightly smaller than the external diameter of the barrel. Two guard collars 32, Figs. 20, 21, keep the rubber ring in position.

The atmospheric communication holes may be drilled through the barrel between the piston and snap or tool as at 27 Figs. 19, 20, or they may be grooves cut parallel to the barrel as at 27, Figs. 24, 25, and communicated to, the atmosphere by diagonal holes as at 27, Figs. 24, 25.

position with the handle end upward. in

the vertical position stated above both the valve F, Figs. 1, 2, 13, 1 1, 17, 18, and the piston S have fallen by gravity to their lowest positions, that is'to say, the valve F restsupon' the miter seat 17, Figs. 6, 10, and the piston 55 rests against the tool R, Figs. 19, 20;

The action of the hammer is 1 as fol Iowa-A. hose conveying high pressure compressed air is united to the screwed nipple J. The tool R is held firmly against the work to be done, the triggerH is then raised and the admission valve G- depressed until the hole K therein comes opposite the hole L which permits the high pressure air- Figs, 11, 12, 15, 16, passes through the holes 8, F igs. 3, 4, 7, and enters the groove 16,

Figs. 5, 6, 10. The valve F beingseated on the miter seat 171,-Figs. 6,10, the hi h pressure air cannot pass into the barrel *1, Figs. 1, 2, so that it then passes from the groove 16, Figs. 5, 6, 10, upward into the holes 25, Figs. 13, 17, 18, of the valve F into the groove 12, F igs. 1, 8, and from there upward through the holes 13, Figs. 7, 8, into the groove 3, Figs. 1, 12, around thenozzle T, Figs. 1, 12, and here the high pressure air, in blowing through the ejector nozzle T and passing out through the ejector discharge U, Figs. 1, 12, induces a vacuum in the nozzle chamber 7, Figs. 1, 2, 12, 16. The vacuum thus created draws the ail out of the barrel E by way of the large hole 2 1,

Figs. 13, 1 1, 18, in the center of the valve F, Figs. 1., 2, 13, 14., 17, 18, the cup shaped hollow 9, Figs. 1, 3, 1, 8, and the holes 6, Figs. 11, 12, 16, and thereby induces a vacuum in the barrel E above the piston S. Atmospheric pressure air entering by the holes 27, Figs. 19, 20, or grooves and holes 27*, 27 Figs.,2=1, 25, between the piston S and the tool R, Figs. 19, 20, 28, forces the piston S upward until it comes in contact with the lower part 21, Figs. 13, 17, of the valve F and by so doing raises the valve F uintil its top portion 19, Figs. 13, 17, with 'seating.*19,'liigs. 13, 17, seats against the seatingf't, Figs. 11, 16. The valve F and nseam the holes 8, Figs. 3, l, 7, this air passes around the small groove 22, Flgs. 13, 14, 17,

and thence upward through the small hole 23, 13, 14, into the space above the valve in the valve chamber 11, Figs. 3, l,

.8. From here the air cannot escape and consequently presses on the valve F in a downward direction. T he piston S having passed the flat relief valve V, Figs. 19, 25, or the rubber relief valve V, liigs. 20, 21

as the case may be according to which type of valve is adopted), the high pressure arr which has driven the piston S'dovvnward- 1s suddenly released through the fiat relief valve holes 28, Figs. 19, 25, or the rubber relief valve holes 28 Figs. 20, 21, (according to which type of valve is adopted) with the result that there is a reduction in pressure in the barrel E above the piston S and below the valve F. The full pressure is, however, maintained above the valve F in the valve chamber 11, Figs. 3, 4:, 8, by communication through the hole 14, Figs; 3, 4t, 8, as before stated, with the result that the valve F is driveu'downward until the miter seats 26, Figs. 13, 17', and 17, Figs. 6 and 10, meet. This brings the ejector again into action, the vacuum is formed and the piston raised for another stroke. As soon as' the ejector starts Work the vacuum is induced.

and the hat relief'valve Figs. 19, 25, is held at its seat 29, Figs. 25, by atmospheric pressure aided by the springs 80, Figs. 25, or, the rubber relief valve V, Figs. 20, 21, is held against the relief holes Figs. 20, 21, aided by its own elasticity,

according to which type of reliei valve adopted. llhe relief valve V or V the may be) being thus. closed. it prevents zfimospheric air from enterir above the niston S, permitting the QjQCiOl to inouce the "ecessary vacmun in the barrel E, as before explained. This cycle is rapidly repeated as long as the trigger H is held up.

it should be particularly noticed that when the valve F is inits bottom position, that is to say, when seated on the miter seat 17', 6, it), he groove 22, Figs. 13, 14, 17, has passed below the hole l t, Figs. 4-, 8, and the compressed air which drove the valve dmvnward can now escape by the hole 15, Figs. and at, into the atmosphere. This device is to insure having as little resistance as po iblc to the raising of the valve if when LllS piston. strikes it new *d. This hole 7 Figs. 3, a, is covered :y the top edge of the main body or the valve 1* as soon as it has traveled upward a short distance. Also it must be observed that when the valve F is in the highest position, with the seatings 19, Figs 13, 17 and 7 Figs. 11,

16, touching, the high pressure air cannot pass up from the barrel E through the hole 2%, Fig. 13, into the nozzle chamber 7, Figs. 12, 1e.

The action of the flat relief valve V, Figs. 19, 25, 28, is that of a non-return valve aided by a steel spring 30, Figs. 22, 25, which holds it lightly against its seat 29, Figs. 22, 25. The action of the rubber ring relief valve V, Figs. 20, 21, is also that of a nonreturn valve aided by its own elasticity which makes it always grip over the barrel E owing to its being smaller in diameter than the barrel and being stretched thereon.

l Vhen the high pressure air presses through.

the holes 28 Figs. 20, 21, it expands the rubber ring valve V and escapes all around and through a number of holes 31, Fig. 20. The guard collars 32, Figs. 20, 21, are intended to keep the rubber ring V in position over the holes 28, Figs. 20, 21, and these guard collars also serve to prevent the hand of the operator from interfering with the working of the rubber rin lVhat I claim as my invention and desire to secure by Letters Patent, is

1. The barrel portion provided with a threaded partat one end, an enlargement at the other end, atmospheric communicating apertures in the lower half of said barrel, relief holes mutt-way of the length of said barrel, and a relief valve controlling said relief aperture, substantially as shown and for the purpose specified.

2. A relief valve comprising a valve seat, portion and a movable thin sheet of metal,- a guiding pin passing through said metal sheet and inserted into the valve seat portion, and a lightspring holding said metal sheet in place against the seat portion, substantially as shown and for the purpose specified.

3. A pneumatic hammer comprising in combination, cylinder provided with a bore, a piston in said bore, a cap on said cylinder having admission ports, a valvein said cap communicating with said bore and comprising a plurality of juxtaposed sections having ports communicating with said capadmission ports and with said bore, an ejector in said box, and a distributing valve in said box controlling admission from said box ports to said bore and eject-or and projecting into the path of said piston for actuation thereby in one direction, said valve having a port for communication with one of said box ports for actuation of said valve in another direction.

4.. A pneumatic hammer comprising in combination, a cylinder provided with a.

bore, a piston in said bore, a cap on said ejector and projecting into the path of said 10 cylinder having admission ports, a valve piston for actuation thereby in one direction.

box in said cap communicating with said In witness whereof I have hereunto set bore and comprising a plurality of juxtamy hand in the presence of two Witnesses.

posed sections havin ports communicating w x w 7 1 with said cap admiss ion portsand with the CLEMENI HLNRl bore, an ejector in said box, and a distribut- Witnesses:

ing valve in said box for controlling admis- I ARTHUR E. EDWARDS,

sion from said box ports to said-bore and l D. K. BoYLn. 

